'There are dozen of available video output drivers and video output options, it will take at least several pages to explain everything about them, but as you can always read more complete manuals and also the MPlayer man pages, the current minitutor is only shows some important and interesting video output you can use to play around your favorite movies and files.
The MPlayer offers dozen of video output options you can use to change the way the video file is showed such as '-brightness', '-contrast', '-fs' fullscreen playback, '-geometry', '-saturation' and more. For example, you can play a video file by setting its color to grayscale and fullscreen by using 'mplayer -fs -saturation -100 file.mpeg'.
Some of these video output options can be also used to video output drivers, you need to read the man page to see what you can use.
The MPlayer video output drivers (-vo) are interfaces to different video ouput facilities, and the syntax to use with -vo option is '-vo driver1:suboption1=value'. The options you can use are great not only to get a better displayed image but also to play around and get pieces of your video file, or even play video out of X Server.
Play video out of X, out of the graphical mode, it's a very important feature we have on MPlayer. In order to play a video file out of X you can use some video output options, such as 'vesa' and fbdev'. The 'fbdev' plays your video file by using the kernel framebuffer and a device you may or may not specify at command line, for example 'mplayer -vo fbdev file.mpeg'.
Another great feature are the options to save the video output to a non video file, for example images and/or an animated gif. In order to save a video file to an animated gif you need to use the option 'gif89a', for example you can use a line like 'mplayer -vo gif89a:15.0:movie.gif file.mpeg'. In the example we change the default output filename which is out.gif to movie.gif and also set the framerate to 15.0 instead of use the default 5.0.
There are also drivers for X you can use to get a better image of your video file, such as 'sdl' which uses the SDL library and 'gl' to use OpenGL driver. Also you can use the 'null' to produces no video output and some others.
One very interesting driver is 'aa', the ASCII art video output driver that works on a text console. You can get very intriguing pictures from your video in ASCII art (picture below). It's really an impressive driver specially because it has several options you can count such as 'extended' which uses all 256 characters, 'driver' which is used to select the aalib driver (X11, curses, linux), and more. The ASCII Art MPlayer accepts rendering options, dithering options, monitor parameters, size options, attributes, font options, and others. It almost a player inside the player. An example: mplayer -vo aa:bold:driver=curses:contrast=50 file.mpeg.
The video output options and video output drivers are only a small percent of the MPlayer's power.
Read the man page and search for other options you can use, and also do not forget to take a look at Mencoder, the MPlayer video encoder.
You have a powerful video and audio player, fell free to play and play around it.